xref: /netbsd-src/sys/arch/arm/xscale/ixp425_intr.c (revision cf0030cb2878780138a787886514b97c57932329)
1 /*	$NetBSD: ixp425_intr.c,v 1.28 2020/11/20 18:49:45 thorpej Exp $ */
2 
3 /*
4  * Copyright (c) 2003
5  *	Ichiro FUKUHARA <ichiro@ichiro.org>.
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY ICHIRO FUKUHARA ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL ICHIRO FUKUHARA OR THE VOICES IN HIS HEAD BE LIABLE FOR
21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 /*
30  * Copyright (c) 2001, 2002 Wasabi Systems, Inc.
31  * All rights reserved.
32  *
33  * Written by Jason R. Thorpe for Wasabi Systems, Inc.
34  *
35  * Redistribution and use in source and binary forms, with or without
36  * modification, are permitted provided that the following conditions
37  * are met:
38  * 1. Redistributions of source code must retain the above copyright
39  *    notice, this list of conditions and the following disclaimer.
40  * 2. Redistributions in binary form must reproduce the above copyright
41  *    notice, this list of conditions and the following disclaimer in the
42  *    documentation and/or other materials provided with the distribution.
43  * 3. All advertising materials mentioning features or use of this software
44  *    must display the following acknowledgement:
45  *      This product includes software developed for the NetBSD Project by
46  *      Wasabi Systems, Inc.
47  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
48  *    or promote products derived from this software without specific prior
49  *    written permission.
50  *
51  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
52  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
53  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
54  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
55  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
56  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
57  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
58  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
59  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
60  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
61  * POSSIBILITY OF SUCH DAMAGE.
62  */
63 
64 #include <sys/cdefs.h>
65 __KERNEL_RCSID(0, "$NetBSD: ixp425_intr.c,v 1.28 2020/11/20 18:49:45 thorpej Exp $");
66 
67 #ifndef EVBARM_SPL_NOINLINE
68 #define	EVBARM_SPL_NOINLINE
69 #endif
70 
71 /*
72  * Interrupt support for the Intel IXP425 NetworkProcessor.
73  */
74 
75 #include <sys/param.h>
76 #include <sys/systm.h>
77 #include <sys/kmem.h>
78 
79 #include <sys/bus.h>
80 #include <machine/intr.h>
81 
82 #include <arm/cpufunc.h>
83 
84 #include <arm/xscale/ixp425reg.h>
85 #include <arm/xscale/ixp425var.h>
86 
87 /* Interrupt handler queues. */
88 struct intrq intrq[NIRQ];
89 
90 /* Interrupts to mask at each level. */
91 int ixp425_imask[NIPL];
92 
93 /* Interrupts pending. */
94 volatile int ixp425_ipending;
95 
96 /* Software copy of the IRQs we have enabled. */
97 volatile uint32_t intr_enabled;
98 
99 /* Mask if interrupts steered to FIQs. */
100 uint32_t intr_steer;
101 
102 #ifdef __HAVE_FAST_SOFTINTS
103 /*
104  * Map a software interrupt queue index
105  *
106  * XXX: !NOTE! :XXX
107  * We 'borrow' bits from the interrupt status register for interrupt sources
108  * which are not used by the current IXP425 port. Should any of the following
109  * interrupt sources be used at some future time, this must be revisited.
110  *
111  *  Bit#31: SW Interrupt 1
112  *  Bit#30: SW Interrupt 0
113  *  Bit#14: Timestamp Timer
114  *  Bit#11: General-purpose Timer 1
115  */
116 static const uint32_t si_to_irqbit[SI_NQUEUES] = {
117 	IXP425_INT_bit31,		/* SI_SOFT */
118 	IXP425_INT_bit30,		/* SI_SOFTCLOCK */
119 	IXP425_INT_bit14,		/* SI_SOFTNET */
120 	IXP425_INT_bit11,		/* SI_SOFTSERIAL */
121 };
122 
123 #define	SI_TO_IRQBIT(si)	(1U << si_to_irqbit[(si)])
124 
125 /*
126  * Map a software interrupt queue to an interrupt priority level.
127  */
128 static const int si_to_ipl[] = {
129 	[SI_SOFTCLOCK] =	IPL_SOFTCLOCK,
130 	[SI_SOFTBIO] =		IPL_SOFTBIO,
131 	[SI_SOFTNET] =		IPL_SOFTNET,
132 	[SI_SOFTSERIAL] =	IPL_SOFTSERIAL,
133 };
134 #endif /* __HAVE_FAST_SOFTINTS */
135 void	ixp425_intr_dispatch(struct clockframe *frame);
136 
137 static inline uint32_t
ixp425_irq_read(void)138 ixp425_irq_read(void)
139 {
140 	return IXPREG(IXP425_INT_STATUS) & intr_enabled;
141 }
142 
143 static inline void
ixp425_set_intrsteer(void)144 ixp425_set_intrsteer(void)
145 {
146 	IXPREG(IXP425_INT_SELECT) = intr_steer & IXP425_INT_HWMASK;
147 }
148 
149 static inline void
ixp425_enable_irq(int irq)150 ixp425_enable_irq(int irq)
151 {
152 
153 	intr_enabled |= (1U << irq);
154 	ixp425_set_intrmask();
155 }
156 
157 static inline void
ixp425_disable_irq(int irq)158 ixp425_disable_irq(int irq)
159 {
160 
161 	intr_enabled &= ~(1U << irq);
162 	ixp425_set_intrmask();
163 }
164 
165 static inline uint32_t
ixp425_irq2gpio_bit(int irq)166 ixp425_irq2gpio_bit(int irq)
167 {
168 
169 	static const uint8_t int2gpio[32] __attribute__ ((aligned(32))) = {
170 		0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* INT#0 -> INT#5 */
171 		0x00, 0x01,				/* GPIO#0 -> GPIO#1 */
172 		0xff, 0xff, 0xff, 0xff, 0xff, 0xff,	/* INT#8 -> INT#13 */
173 		0xff, 0xff, 0xff, 0xff, 0xff,		/* INT#14 -> INT#18 */
174 		0x02, 0x03, 0x04, 0x05, 0x06, 0x07,	/* GPIO#2 -> GPIO#7 */
175 		0x08, 0x09, 0x0a, 0x0b, 0x0c,		/* GPIO#8 -> GPIO#12 */
176 		0xff, 0xff				/* INT#30 -> INT#31 */
177 	};
178 
179 #ifdef DEBUG
180 	if (int2gpio[irq] == 0xff)
181 		panic("ixp425_irq2gpio_bit: bad GPIO irq: %d\n", irq);
182 #endif
183 	return (1U << int2gpio[irq]);
184 }
185 
186 /*
187  * NOTE: This routine must be called with interrupts disabled in the CPSR.
188  */
189 static void
ixp425_intr_calculate_masks(void)190 ixp425_intr_calculate_masks(void)
191 {
192 	struct intrq *iq;
193 	struct intrhand *ih;
194 	int irq, ipl;
195 
196 	/* First, figure out which IPLs each IRQ has. */
197 	for (irq = 0; irq < NIRQ; irq++) {
198 		int levels = 0;
199 		iq = &intrq[irq];
200 		ixp425_disable_irq(irq);
201 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
202 		     ih = TAILQ_NEXT(ih, ih_list))
203 			levels |= (1U << ih->ih_ipl);
204 		iq->iq_levels = levels;
205 	}
206 
207 	/* Next, figure out which IRQs are used by each IPL. */
208 	for (ipl = 0; ipl < NIPL; ipl++) {
209 		int irqs = 0;
210 		for (irq = 0; irq < NIRQ; irq++) {
211 			if (intrq[irq].iq_levels & (1U << ipl))
212 				irqs |= (1U << irq);
213 		}
214 		ixp425_imask[ipl] = irqs;
215 	}
216 
217 	KASSERT(ixp425_imask[IPL_NONE] == 0);
218 
219 #ifdef __HAVE_FAST_SOFTINTS
220 	/*
221 	 * Initialize the soft interrupt masks to block themselves.
222 	 */
223 	ixp425_imask[IPL_SOFTCLOCK] = SI_TO_IRQBIT(SI_SOFTCLOCK);
224 	ixp425_imask[IPL_SOFTBIO] = SI_TO_IRQBIT(SI_SOFTBIO);
225 	ixp425_imask[IPL_SOFTNET] = SI_TO_IRQBIT(SI_SOFTNET);
226 	ixp425_imask[IPL_SOFTSERIAL] = SI_TO_IRQBIT(SI_SOFTSERIAL);
227 #else
228 	KASSERT(ixp425_imask[IPL_SOFTCLOCK] == 0);
229 	KASSERT(ixp425_imask[IPL_SOFTBIO] == 0);
230 	KASSERT(ixp425_imask[IPL_SOFTNET] == 0);
231 	KASSERT(ixp425_imask[IPL_SOFTSERIAL] == 0);
232 #endif
233 
234 	/*
235 	 * Enforce a hierarchy that gives "slow" device (or devices with
236 	 * limited input buffer space/"real-time" requirements) a better
237 	 * chance at not dropping data.
238 	 */
239 	ixp425_imask[IPL_SCHED] |= ixp425_imask[IPL_VM];
240 	ixp425_imask[IPL_HIGH] |= ixp425_imask[IPL_SCHED];
241 
242 	/*
243 	 * Now compute which IRQs must be blocked when servicing any
244 	 * given IRQ.
245 	 */
246 	for (irq = 0; irq < NIRQ; irq++) {
247 		int irqs = (1U << irq);
248 		iq = &intrq[irq];
249 		if (TAILQ_FIRST(&iq->iq_list) != NULL)
250 			ixp425_enable_irq(irq);
251 		for (ih = TAILQ_FIRST(&iq->iq_list); ih != NULL;
252 		     ih = TAILQ_NEXT(ih, ih_list))
253 			irqs |= ixp425_imask[ih->ih_ipl];
254 		iq->iq_mask = irqs;
255 	}
256 }
257 
258 void
splx(int new)259 splx(int new)
260 {
261 	ixp425_splx(new);
262 }
263 
264 int
_spllower(int ipl)265 _spllower(int ipl)
266 {
267 	return (ixp425_spllower(ipl));
268 }
269 
270 int
_splraise(int ipl)271 _splraise(int ipl)
272 {
273 	return (ixp425_splraise(ipl));
274 }
275 
276 /*
277  * ixp425_icu_init:
278  *
279  * 	Called early in bootstrap to make clear interrupt register
280  */
281 void
ixp425_icu_init(void)282 ixp425_icu_init(void)
283 {
284 
285 	intr_enabled = 0;	/* All interrupts disabled */
286 	ixp425_set_intrmask();
287 
288 	intr_steer = 0;		/* All interrupts steered to IRQ */
289 	ixp425_set_intrsteer();
290 }
291 
292 /*
293  * ixp425_intr_init:
294  *
295  *	Initialize the rest of the interrupt subsystem, making it
296  *	ready to handle interrupts from devices.
297  */
298 void
ixp425_intr_init(void)299 ixp425_intr_init(void)
300 {
301 	struct intrq *iq;
302 	int i;
303 
304 	intr_enabled = 0;
305 
306 	for (i = 0; i < NIRQ; i++) {
307 		iq = &intrq[i];
308 		TAILQ_INIT(&iq->iq_list);
309 
310 		snprintf(iq->iq_name, sizeof(iq->iq_name), "irq %d", i);
311 	}
312 
313 	ixp425_intr_calculate_masks();
314 
315 	/* Enable IRQs (don't yet use FIQs). */
316 	enable_interrupts(I32_bit);
317 }
318 
319 void
ixp425_intr_evcnt_attach(void)320 ixp425_intr_evcnt_attach(void)
321 {
322 	struct intrq *iq;
323 	int i;
324 
325 	for (i = 0; i < NIRQ; i++) {
326 		iq = &intrq[i];
327 		evcnt_attach_dynamic(&iq->iq_ev, EVCNT_TYPE_INTR,
328 		    NULL, "ixp425", iq->iq_name);
329 	}
330 }
331 
332 void *
ixp425_intr_establish(int irq,int ipl,int (* func)(void *),void * arg)333 ixp425_intr_establish(int irq, int ipl, int (*func)(void *), void *arg)
334 {
335 	struct intrq *iq;
336 	struct intrhand *ih;
337 	u_int oldirqstate;
338 
339 	if (irq < 0 || irq > NIRQ)
340 		panic("ixp425_intr_establish: IRQ %d out of range", irq);
341 #ifdef DEBUG
342 	printf("ixp425_intr_establish(irq=%d, ipl=%d, func=%08x, arg=%08x)\n",
343 	       irq, ipl, (uint32_t) func, (uint32_t) arg);
344 #endif
345 
346 	ih = kmem_alloc(sizeof(*ih), KM_SLEEP);
347 	ih->ih_func = func;
348 	ih->ih_arg = arg;
349 	ih->ih_ipl = ipl;
350 	ih->ih_irq = irq;
351 
352 	iq = &intrq[irq];
353 
354 	/* All IXP425 interrupts are level-triggered. */
355 	iq->iq_ist = IST_LEVEL; /* XXX */
356 
357 	oldirqstate = disable_interrupts(I32_bit);
358 
359 	TAILQ_INSERT_TAIL(&iq->iq_list, ih, ih_list);
360 
361 	ixp425_intr_calculate_masks();
362 
363 	restore_interrupts(oldirqstate);
364 
365 	return (ih);
366 }
367 
368 void
ixp425_intr_disestablish(void * cookie)369 ixp425_intr_disestablish(void *cookie)
370 {
371 	struct intrhand *ih = cookie;
372 	struct intrq *iq = &intrq[ih->ih_irq];
373 	int oldirqstate;
374 
375 	oldirqstate = disable_interrupts(I32_bit);
376 
377 	TAILQ_REMOVE(&iq->iq_list, ih, ih_list);
378 
379 	ixp425_intr_calculate_masks();
380 
381 	restore_interrupts(oldirqstate);
382 }
383 
384 void
ixp425_intr_dispatch(struct clockframe * frame)385 ixp425_intr_dispatch(struct clockframe *frame)
386 {
387 	struct intrq *iq;
388 	struct intrhand *ih;
389 	int oldirqstate, irq, ibit, hwpend;
390 	struct cpu_info * const ci = curcpu();
391 	const int ppl = ci->ci_cpl;
392 	const uint32_t imask = ixp425_imask[ppl];
393 
394 	hwpend = ixp425_irq_read();
395 
396 	/*
397 	 * Disable all the interrupts that are pending.  We will
398 	 * reenable them once they are processed and not masked.
399 	 */
400 	intr_enabled &= ~hwpend;
401 	ixp425_set_intrmask();
402 
403 	while (hwpend != 0) {
404 		irq = ffs(hwpend) - 1;
405 		ibit = (1U << irq);
406 
407 		hwpend &= ~ibit;
408 
409 		if (imask & ibit) {
410 			/*
411 			 * IRQ is masked; mark it as pending and check
412 			 * the next one.  Note: the IRQ is already disabled.
413 			 */
414 			ixp425_ipending |= ibit;
415 			continue;
416 		}
417 
418 		ixp425_ipending &= ~ibit;
419 
420 		iq = &intrq[irq];
421 		iq->iq_ev.ev_count++;
422 		ci->ci_data.cpu_nintr++;
423 
424 		/* Clear down non-level triggered GPIO interrupts now */
425 		if ((ibit & IXP425_INT_GPIOMASK) && iq->iq_ist != IST_LEVEL) {
426 			IXPREG(IXP425_GPIO_VBASE + IXP425_GPIO_GPISR) =
427 			    ixp425_irq2gpio_bit(irq);
428 		}
429 
430 		TAILQ_FOREACH(ih, &iq->iq_list, ih_list) {
431 			ci->ci_cpl = ih->ih_ipl;
432 			oldirqstate = enable_interrupts(I32_bit);
433 			(void) (*ih->ih_func)(ih->ih_arg ? ih->ih_arg : frame);
434 			restore_interrupts(oldirqstate);
435 		}
436 
437 		/* Clear down level triggered GPIO interrupts now */
438 		if ((ibit & IXP425_INT_GPIOMASK) && iq->iq_ist == IST_LEVEL) {
439 			IXPREG(IXP425_GPIO_VBASE + IXP425_GPIO_GPISR) =
440 			    ixp425_irq2gpio_bit(irq);
441 		}
442 
443 		ci->ci_cpl = ppl;
444 
445 		/* Re-enable this interrupt now that's it's cleared. */
446 		intr_enabled |= ibit;
447 		ixp425_set_intrmask();
448 
449 		/*
450 		 * Don't forget to include interrupts which may have
451 		 * arrived in the meantime.
452 		 */
453 		hwpend |= ((ixp425_ipending & IXP425_INT_HWMASK) & ~imask);
454 	}
455 
456 #ifdef __HAVE_FAST_SOFTINTS
457 	cpu_dosoftints();
458 #endif
459 }
460